<!doctype html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport"
        content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>Document</title>
  <style>
    *{
      margin: 0;
      padding: 0;
    }
    .container{
      position: relative;
      padding: 0 200px;
    }
    .container>div{
      position: absolute;
      height: 200px;
    }
    .left{
      top: 0;
      left: 200px;
      width: 200px;
      margin-left: -200px;
      background-color: red;
    }
    .right{
      top: 0;
      right: 200px;
      width: 200px;
      margin-right: -200px;
      background-color: green;
    }
    .middle{
      width: 100%;
      background-color: yellow;
    }
  </style>
</head>
<body>
  <div class="container">
    <div class="left">左</div>
    <div class="middle">中</div>
    <div class="right">右</div>
  </div>
</body>
</html>
